I believe I have seen this haiku from Issa before somewhere, maybe from one of your previous blogs. But I never thought it could be read like: Chrysanthemum is just the crest of imperial house. Issa was trying to express his disapproval at the shogunate! If so, this haiku becomes so meaningful and intriguing which I would love so much!

Oh, I posted another comment on your blog: Today in Japan Sep 11 ~ More Drama From the Shogunate!
I wish I could get the accurate answer from you!

Please watch this vedio clip:
https://v.douyin.com/6yD8cry/